蒺藜苜蓿全基因组发育调控重要基因WOX家族的鉴定和生物信息学分析

Identification and Bioinformatics Analysis of the Genes Regulating the Development of Medicago truncatula

在拟南芥中的研究显示,WOX蛋白调节植物的关键发育,在植物发育中起着广泛作用。我们应用多种生物信息学手段,从蒺藜苜蓿全基因组中筛选、鉴定了WOX家族成员,并进行基本特征、染色体定位、系统进化、表达特征等分析。蒺藜苜蓿基因组中共存在17个WOX基因,这些基因的分子量和等电点分布范围较广,但是有一定的聚集特征。绝大多数蒺藜苜蓿WOX基因都是小于300个氨基酸,等电点位于pH 5~7之间,但是有个别例外。与拟南芥WOX基因家族相同,蒺藜苜蓿WOX基因可分为3个系统进化分枝,分别是WUS,中间进化枝和古代进化枝。在蒺藜苜蓿4号和7号染色体上,有WOX基因聚集的位点。而且这两个WOX基因聚集位点上的基因具有较近的亲缘关系。Medtr4g084550.1和Medtr7g060630.1同属于WUS亚家族,聚集在一个进化分枝上。Medtr4g088070.1、Medtr4g088080.1和Medtr7g025010.1同属于中间进化枝,序列相似度同样非常高。蒺藜苜蓿WOX基因在各个器官中表达特异性非常高。根部和根尖中表达的WOX基因完全不同。外界胁迫处理,包括盐处理和根腐病菌侵染,会引起蒺藜苜蓿WOX基因表达的变化。

Studies in Arabidopsis have shown that WOX genes regulates critical plant development and plays a broad role in plant development. We used a variety of bioinformatics methods to screen and identify members of the WOX family from the whole genome of Medicago truncatula, and analyzed the basic characteristics,chromosomal location, phylogenetic evolution and expression characteristics of these WOX genes. There were 17 WOX genes in the genome of M. truncatum. Most WOX genes of M. truncatula were less than 300 amino acids and the isoelectric point was between pH 5-7. There were some exceptions. Similar to the WOX gene family of Arabidopsis thaliana, WOX genes of M. truncatula can be divided into three phylogenetic clades, namely WUS,intermediate clade and ancient clade. There were sites of WOX gene clusters on the 4 th and 7 th chromosomes of Medicago truncatula. And the WOX genes of these two clusters were closely related to each other. Medtr4 g084550.1 and Medtr7 g060630.1 belong to the WUS subfamily, clustered on one evolutionary branch. Medtr4 g088070.1,Medtr4 g088080.1 and Medtr7 g025010.1 belong to the same clade. The sequence similarity is also very high. The specificity of WOX gene expression in various organs of M. truncatula is very high. The WOX genes expressed in roots and root tips were completely different. External stress treatment, including salt treatment and root rot pathogen infection, could cause changes in the expression of WOX genes in Medicago truncatula.